RunConfigurationAspect: Streamline data serialization

Change-Id: I6f49dd9eeff53eafc51bd5238ca655437df12111
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>
Reviewed-by: Daniel Teske <daniel.teske@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>

src/plugins/projectexplorer/runconfiguration.cpp

@@ -224,7 +224,7 @@ QVariantMap RunConfiguration::toMap() const
     QVariantMap map = ProjectConfiguration::toMap();
 
     foreach (IRunConfigurationAspect *aspect, m_aspects)
-        map.unite(aspect->toMap());
+        aspect->toMap(map);
 
     return map;
 }